Is it not 15% slower for every star and/or every year of age?
So a 19 year old will train 15% slower than an 18 year old if for example they both play the same position, get the same drills and are training up from (for example) 80-100%. Likewise the same 19 year old training from 100-120% will train 15% slower than another 19 year old (same position, same drills) going from 80-100%.?
That's how I understand the process to work. Right or wrong? Go!